The present invention results from a research, which has been carried out as a part of work which was supported by ICT R&D program of MSIP/IITP [10043450, Development of Video Server Technology for Capturing, Editing, Ingesting, and Transmitting 8K and S3D 4K UHD Contents], and supported by the Technology Innovation Program (10049498, 4K UHD HEVC/VP9 SoC for Streaming Smart Device) funded by the Ministry of Trade, Industry and Energy (MOTIE, KOREA).
Recent improvement of video processing algorithms allows a video processing apparatus to process much larger-scale images.
Specifically, with need for ultrahigh definition (UHD), existing video compression techniques have difficulty in accommodating sizes of storage media and bandwidths of transfer media. Accordingly, a novel standard for compression of UHD video is needed. As a result, high efficiency video coding (HEVC) has completely been standardized on January in 2013. The HEVC may be available for a video stream serviced through networks, such as the Internet, 3G, long term evaluation (LTE), etc, in which not only UHD but also full high definition (FHD) or high definition (HD) videos can be compressed in accordance with HEVC.
A UHD TV is considered to mainly provide 4K (4096×2304 pixels) UHD at 30 frames per second (fps) in the short term, while the number of pixels to be processed per second is expected to continuously increase to 4K 60 fps/120 fps, 8K 30 fps/60 fps, and the like. A bandwidth on demand per frame for a bidirectional frame prediction and filtering is expected to remarkably increase as well.
To deal with the increase in the processing bandwidths, a transmission bandwidth between system modules or to the exterior should also be improved based on performance or functions required for applications.
However, unlike the remarkable increase in the required processing bandwidth in response to an increase in image resolutions to be processed and frame rates, a bandwidth for transmission thereof is limited.
For example, a bandwidth for storing an image in a frame buffer memory or extracting the image from the frame buffer memory may be limited according to a minimum burst length of a memory application.
To overcome this problem, a method of compressing images which are input and/or output in/out the frame buffer memory is taken into account, but fails to provide a remarkable bandwidth reduction effect.
Also, current frame buffer compression techniques are using a loss compression algorithm for obtaining high compression efficiency. However, the loss compression algorithm brings about a gradual decrease of quality and a change of a compression data format.
Due to the format change, a process of searching for a frame buffer memory for random access is made complicated, thereby increasing a throughput and a processing time again.